This invention relates generally to log handling systems for use in the woods or other elongated object handling systems, but more particularly to a remotely controlled choker hook and release system.
It is common practice in woods operations where trees are being harvested and logs moved about to utilize cable handling systems either at ground level or overhead yarding systems. As a part of these log handling systems, steel cables are wrapped about felled trees to form a noose or choker. The cable, once looped around a tree or a plurality of trees, is attached back onto itself, using a special device referred to as a choker hook which allows the loop to tighten about the tree. The tightened loop serves to hold it as the cable is then tensioned to lift the tree and pull it to the desired location. Once the logs arrive at the desired location, the choker must then be released in order to release the tree. The typical way choker hooks are now released is by manual labor, physically releasing the choker hook after the cable is slackened and the loop removed from the tree. Not only is the job of releasing the chokers extremely dangerous, but it takes time and delays production.
In the past, others have designed remotely controlled selfreleasing choker mechanisms and one such example may be seen by referring to U.S. Pat. No. 3,104,909 issued in 1963 to W. M. Walker. In the Walker patent, a choker hook is disclosed where the end of a cable has a ferrule affixed to it which is seated and held within the choker hook casing. A pivotally mounted locking arm is controlled in part by a servo for holding and releasing the end of the cable. There are certain shortcomings in the Walker choker hook, among them being its lack of flexibility, openness, complexity, size and cost. These disadvantages have been overcome by the subject matter of the present invention.
Accordingly from the foregoing, one object of the present invention is the provision of a small, highly reliable self-contained remotely controlled choker hook mechanism.
Another object of the invention is to provide a self-releasing choker hook capable of grasping and releasing cables with either loops or ferrules on their ends.
Yet a further object of this invention is to provide a mechanism which can be manufactured and operated at a low cost.
These and other objects of the invention will be better understood and appreciated upon a thorough review of the specification to follow in conjunction with the attached drawings.